Safety system for fueling vehicle

ABSTRACT

The invention is an improved method and system to fuel a vehicle. The present invention includes a strategy to determine whether the vehicle is ready to receive fuel and to communicate a vehicle confirmation signal (VCS) to the fuel fill station when the strategy has determined the vehicle is ready to receive fuel. The strategy also includes a dispenser activation system comprising a device to receive the VCS and generate a second signal within the fuel fill station to release the fuel dispenser and fuel dispenser nozzle when the VCS is received. A vehicle locking system can be added to disable the vehicle while the vehicle fuel door is open or when the fuel station nozzle is attached to the vehicle nozzle receptacle. The strategy can determine whether the vehicle is ready to receive fuel by requiring the gearshift device to be in the “Park” position. If the vehicle has a manual transmission, the strategy requires the parking brake to be applied. Other required determinations, such as main power circuit off and emergency power circuit on, can also be added. The VCS communication can be by radio frequency (“RF”) signal, direct wire, or infrared (“IR”) signal. The direct wire communication can use threshold currents from a VCS circuit.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates generally to a vehicle fueling system and specifically to a method and system to signal a fueling station it is safe to fuel the vehicle and disabling the vehicle until fueling is complete.

[0003] 2. Discussion of the Prior Art

[0004] In an effort to find alternative energy sources, hydrogen can be used in an electrochemical reaction to generate electricity. Generally, the reaction takes place in fuel cells. Fuel cells are known in the prior art for directly converting chemical energy of a fuel to electrical energy. Fuel cell advantages include low emissions, high fuel energy conversion efficiencies, and low noise and vibrations (U.S. Pat. No. 5,248,566 to Kumar, et al.) Despite the advantages, various problems are presented by existing fuel cell technology.

[0005] Fuel cell systems are typically fueled with hydrogen. Hydrogen fueling and storing can be extremely dangerous due to its highly flammable nature. When a hydrogen vehicle receives fuel, the vehicle is usually mechanically locked to a nozzle on the dispensing line from the fill station. If the connection from the fill station to the vehicle is improper or the vehicle operator attempts to drive away before the dispensing line is returned to the fill station, tragic consequences could result.

[0006] Ways to reduce risks associated with the transfers of fuels are known in the prior art. For example, U.S. Pat. No. 4,091,848 to Phillips discloses a safety warning system for a liquefied petroleum (“LP”) gas transport vehicle. The system informs a vehicle's operator of a hose connection extending between a vehicle's gas tank and a second remote main supply.

[0007] U.S. Pat. No. 5,156,198 to Hall discloses a pump lock fuel system. The patent describes a fuel lock and dispensing system where data from a vehicle computer is used to identify the vehicle, to transfer data to and from the vehicle computer to a fuel pump computer, and to unlock the fuel pump. The system will only allow fueling after a fuel nozzle is inserted and a vehicle identified. Although this patent provides an element of safety, its primary function is vehicle identification.

[0008] Automatic refueling systems are also known in the prior art. For example, U.S. Pat. No. 5,383,500 to Dwars et al. discloses an automatic refueling system where the driver does not need to leave the vehicle, but allows the driver to interrupt or modify refueling. See also, U.S. Pat. No. 4,608,830 to Peschka et al. and U.S. Pat. No. 3,502,117 to Nebelsiek et al.

[0009] Unfortunately, the prior art seems more concerned with fueling efficiency rather than safety. A safer method and system to specifically address the inherent dangers of fuel transfer is needed. This is of particular importance for the safe implementation of hydrogen fueled vehicles.

SUMMARY OF THE INVENTION

[0010] Accordingly, the present invention provides an improved and safer system and method to fuel a vehicle. An object of the present invention includes a strategy to determine whether the vehicle is ready to receive fuel and to communicate a vehicle confirmation signal (VCS) that is communicated to the fuel fill station when the strategy has determined the vehicle is ready to receive fuel. The strategy also includes a dispenser activation system comprising a device to receive the VCS and generate a second signal within the fuel fill station to release the fuel dispenser and fuel dispenser nozzle when the VCS is received.

[0011] Another object of the present invention also includes a vehicle locking system to disable the vehicle while the vehicle fuel door is open or when the fuel fill station nozzle is attached to the vehicle nozzle receptacle.

[0012] Another object of the present invention can include a strategy to determine whether the vehicle is ready to receive fuel by requiring the gearshift device to be in the “Park” position. If the vehicle has a manual transmission, the strategy requires the parking brake to be applied. Other required determinations, such as main power circuit off and emergency power circuit on, can also be added.

[0013] The VCS communication can be by radio frequency (“RF”) signal, direct wire, or infrared (“IR”) signal. The direct wire communication can use threshold currents from a VCS circuit.

[0014] Other objects of the present invention will become more apparent to persons having ordinary skill in the art to which the present invention pertains from the following description taken in conjunction with the accompanying figures.

BRIEF DESCRIPTION OF THE FIGURES

[0015] The foregoing objects, advantages, and features, as well as other objects and advantages, will become apparent with reference to the description and figures below, in which like numerals represent like elements and in which:

[0016]FIG. 1 illustrates a possible vehicle confirmation signal (VCS) strategy;

[0017]FIG. 2 illustrates a possible “confirmed” VCS circuit; and

[0018]FIG. 3 illustrates a possible “not confirmed” VCS circuit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0019] The present invention relates to fuel transfer and specifically to a method and system to make fueling a vehicle safer. A safer fueling method and system are of particular importance for the safe and successful implementation of vehicles powered by new sources of fuel such as hydrogen. Although the illustrated embodiments of the present invention are particularly suited to hydrogen fueling, the present invention itself can be adapted to most types of fuel by someone of ordinary skill in the art.

[0020] In general, when a vehicle, such as an electric vehicle propelled by hydrogen fueled fuel cells, ends its drive cycle when triggered by a “key-off,” the following steps should be taken. First, a vehicle gearshift lever should be placed in “Park” if the vehicle has an automatic transmission. Additionally (or alternately for a manual transmission vehicle), a parking brake should be applied. Next, the vehicle's main electrical power circuit should be turned off. This main power circuit cutoff switch disconnects at least one pole of an on-board electrical power source such as a battery. This can be a manual switch positioned within an operator's reach. This disconnect device may be the same device for the vehicle's power-on procedure.

[0021] If the vehicle needs refueling, additional conditions can be required. The vehicle should have a fuel door and a receptacle to mechanically receive a fuel dispenser nozzle from a fuel fill station. The fuel fill station also has a fuel dispenser line and a fuel line dispensing release.

[0022] A vehicle emergency power off (EPO) circuit should be present and retain power during fueling. This circuit can provide electrical power to any detection or alarm systems that may be on the vehicle such as fuel detectors and malfunction alarms. The EPO circuit can be controlled by an EPO circuit switch. The EPO can also be a power source for active venting of hydrogen from the vehicle. This circuit bypasses the main power circuit cutoff switch.

[0023] Additionally, a vehicle locking system can be present to disable the vehicle while, for example, the fuel door is open and/or the parking brake is applied. Since the fuel dispenser nozzle is mechanically locked to the vehicle fuel receptacle, a device could prevent the gearshift lever from being moved out of the “Park” position until the fuel door was closed. This would prevent the operator from driving away from the fuel fill station without disconnecting the fuel dispenser nozzle.

[0024] The fuel fill station would probably not need to include any “break-away” features since this would release fuel such as hydrogen if severed and potentially cause detrimental effects if ignited. If the vehicle is already out of “Park,” opening the fuel door should not prevent the vehicle from its normal operation.

[0025] A possible strategy to add safety during fueling is illustrated in FIG. 1. For this strategy, several conditions must be met before fueling is allowed. Further, the strategy can also be configured to disable the vehicle from operation until fueling is complete. Many other possible configurations and conditions to allow fueling or disabling the vehicle are possible and FIG. 1 is provided to illustrate just one possible strategy.

[0026] strategy in FIG. 1 begins with a vehicle “Key-off” 20. In general, the strategy scrolls through various vehicle status inputs to determine if the vehicle is ready to accept fuel. In any step if a determination is no, the strategy can begin all over again for any set period of time. In Step 22, the strategy determines whether the vehicle gearshift is in the “Park” position. This, of course, requires the vehicle to have an automatic transmission. If yes, the strategy moves to Step 24 and determines whether the vehicle parking brake is applied. If yes, the strategy moves to Step 28 and determines whether the main power circuit has been turned off by the main power circuit cutoff switch. If yes, the strategy moves to Step 30 and determines whether the EPO circuit has been activated. If yes, the strategy determines whether the vehicle is ready to receive fuel and generates a vehicle confirmation signal (VCS) as “confirmed” at Step 32 that is communicated to the fuel fill station. A dispenser activation system within the fuel fill station responds by generating a second signal to release of fuel dispenser line and fuel dispenser nozzle.

[0027] The strategy at Step 32 can also disable the vehicle to prevent it from driving away until fueling is complete. This can be accomplished by preventing the release of the parking brake or preventing the vehicle from being shifted out of “Park.” During fueling, the strategy continues to monitor the status of the fuel door at Step 34. If the fuel door is open at Step 34, the strategy generates a command at Step 36 to prevent the vehicle from moving out of park and releasing the parking brake. Once the fuel door is closed at Step 34, the strategy ends and normal vehicle operation may resume.

[0028] Returning to the vehicle confirmation signal (VCS) referenced in the strategy of FIG. 1. As stated previously, the VCS signals to the fuel fill station that the vehicle is ready to accept fuel, to release the fuel fill station dispensing line and to allow the fuel fill station dispensing line to be connected to the vehicle. The VSC can be embodied in a variety of ways. The vehicle can transmit the VSC to the fuel fill station directly through a wiring path or indirectly through a radio frequency (“RF”) or infrared (“IR”) signal. As for the indirect signal embodiments, IR signals are a directional signal from the vehicle to the fuel fill station and may not be the best choice. An RF signal would probably be the preferred VCS embodiment. A VCS using a direct signal requires an electrical connector between the vehicle and the fuel fill station. The RF VCS would eliminate this additional interface and use a more transparent means. The vehicle operator would not have to connect any additional device other than the fuel dispenser nozzle while at the fuel fill station.

[0029]FIGS. 2 and 3 illustrate a possible circuit for the VCS using a direct signal. FIG. 2 illustrates the VCS in its “confirmed” state, while FIG. 3 illustrates its “not confirmed” state (i.e., prior to Step 32). The Figures illustrate a vehicle input circuit 38 as switches to logic devices that turn on a transistor and returns a 8.2 V 46 signal sent from the fuel fill station. A main power circuit cutoff switch is identified by a (M) 40, a gearshift “Park” position is identified as a (P) 44, and an EPO is identified as an (E) 42. The transistor or other switching device is only the direct wiring method of submitting this “confirmation” signal to the fuel fill station. A fuel fill station circuit 46 is also present. The circuitry between the vehicle input circuits 38 and the fuel fill station circuit 46 is a VCS circuit 48. The vehicle inputs presented in FIGS. 2 and 3 are for demonstration only. Various vehicle architectures may add or delete input from these. The “confirmed” state of FIG. 2 exists because in the present configuration the (M) 40 is off, (E) 42 is on, and (P) 44 is activated because it is not grounded. The (P) 44 could also be configured to be grounded to indicate the gearshift is in “Park.” The fuel fill station circuit 46 has an 8.2 V intrinsic safe power 50 to the VCS circuit 48. The VCS circuit 48 checks the inputs from the vehicle input circuits 38. If the vehicle is ready to accept fuel, the transistor circuits (or any type of switching circuit) in the VCS circuit 48 pass a level of current back to the fuel fill station circuit 46. In this instance, a 2.2 mA threshold is required to either have or not to have confirmation. The VCS circuit 48 passes approximately a 5.4 mA 54 for “confirmed” on FIG. 2 and approximately a 0.0429 mA 56 for “not confirmed” on FIG. 3. The fuel fill station circuit 46 could also monitor voltage as it varies from a 2.7 V 58 for “confirmed” on FIG. 2 to a 8.1 V 60 for “not confirmed” on FIG. 3.

[0030] To assist in following the flow of current through the circuits illustrated in FIGS. 2 and 3, the current flows in a counterclockwise motion through various components that are well know in the prior art. They additionally include for the vehicle input circuit 38: a ground 62 and a ground 64. They additionally include for the fuel fill station circuit 46: a ground 66 and an 1 K ohm resistor 68.

[0031] The VCS circuit 48 additionally includes as illustrated: grounds 70, 72, 74, and 76; transistors 78, 80, and 82; resisters 84, 86, 88, 90, 92, 94, 96, 98, 100, and 102 at 10 k ohm, 1 k ohm, 1.5 k ohm, 1 k ohm, 1 k ohm, 8.2 k ohm, 2.2 k ohm, 1.5 k ohm, 10 k ohm, and 2.4 k ohm respectively; and capacitors 104, 106, 108, 110, 112, and 114 at 10 nano-farads, 22 pico-farads, 10 nano-farads, 10 nano-farads, 22 pico-farads, and 22 pico-farads respectively.

[0032] The above-described embodiment of the invention is provided purely for purposes of example. Many other variations, modifications, catalysts, and applications of the invention may be made. In addition, this method not only applies to fuel cell systems but also to any hydrogen production. 

We claim:
 1. A system to transfer fuel, comprising: a fuel fill station comprising a fuel dispenser line, a fuel dispenser line release, and a fuel dispenser nozzle; a vehicle comprising a receptacle to mechanically receive the fuel dispenser nozzle, a strategy to determine the vehicle is ready to receive fuel, and a vehicle confirmation signal (“VCS”) that is communicated to the fuel fill station when the strategy has determined the vehicle is ready to receive fuel; and a dispenser activation system comprising a device to receive the VCS and generate a second signal within the fuel fill station to release the fuel dispenser line and fuel dispenser nozzle when the VCS is received.
 2. The system of claim 1, further comprising a vehicle fuel door and a vehicle locking system to disable the vehicle while the vehicle fuel door is open.
 3. The system of claim 1, further comprising a vehicle locking system to disable the vehicle while the fuel dispenser nozzle is attached to the vehicle nozzle receptacle.
 4. The system of claim 1, wherein the vehicle further comprises an automatic transmission and a gearshift device, and the strategy to determine the vehicle is ready to receive fuel comprises a requirement that the gearshift device be in a “Park” position.
 5. The system of claim 1, wherein the vehicle further comprises a manual transmission and a parking brake, and the strategy to determine the vehicle is ready to receive fuel comprises a requirement that the parking brake be applied.
 6. The system of claim 1, wherein VCS communication comprises a radio frequency (“RF”) signal.
 7. The system of claim 1, wherein VCS communication comprises a direct wire signal.
 8. The system of claim 7, wherein the direct wire signal uses threshold current.
 9. The system of claim 1, wherein VCS communication comprises an infrared (IR) signal.
 10. The system of claim 1, wherein the vehicle further comprises an electrical power source, a main power circuit, a main power circuit cutoff switch, an emergency power off (EPO) circuit, and an EPO circuit switch.
 11. The system of claim 10, wherein the strategy to determine the vehicle is ready to receive fuel comprises a requirement that the main power circuit cutoff switch is manually activated by a vehicle operator.
 12. The system of claim 10, wherein the vehicle further comprises: fuel detectors, malfunction alarms, and an active ventilation system, all powered by the EPO circuit.
 13. The system of claim 12, wherein the step determining whether the vehicle is ready to receive fuel comprises the requirement that the fuel detectors detect no fuel vapors, no malfunction alarms are activated, and the active ventilation systems are functioning normally.
 14. A fueling method, comprising the steps of: determining whether a vehicle is ready to receive fuel; communicating a vehicle confirmation signal (“VCS”) to a fuel fill station when the vehicle is ready to receive fuel; activating a device to receive the VCS and generating a second signal within the fuel fill station releasing a fuel dispenser line and fuel dispenser nozzle after receiving the VCS; and dispensing fuel to the vehicle.
 15. The fueling method of claim 14, further comprising the step of disabling the vehicle until after closing a vehicle fuel door.
 16. The fueling method of claim 14, further comprising the step of disabling the vehicle while a fuel dispenser nozzle is attached to a vehicle nozzle receptacle.
 17. The fueling method of claim 14, wherein determining whether a vehicle comprising an automatic transmission and a gearshift device is ready to receive fuel, further comprises the step of requiring the gearshift device be in a “Park” position.
 18. The fueling method of claim 14, wherein determining whether a vehicle comprising a manual transmission and a parking brake is ready to receive fuel, further comprises the step of requiring applying the parking brake.
 19. The fueling method of claim 14, wherein the step of communicating a VCS comprises using a radio frequency (“RF”) signal.
 20. The fueling method of claim 14, wherein the step of communicating a VCS comprises using direct wire signal.
 21. The fueling method of claim 14, wherein the step of communicating a VCS comprises using an infrared (IR) signal.
 22. The fueling method of claim 14, wherein the step determining whether a vehicle is ready to receive fuel comprises the step of requiring activating manually a main power circuit cutoff switch.
 23. The fueling method of claim 14, wherein determining whether a vehicle is ready to receive fuel comprises the step of requiring detecting no fuel vapors, activating no malfunction alarms, and active ventilation systems functioning normally. 